The present invention relates to aircraft and more specifically, but not exclusively, to passenger aircraft with wing tip devices.
There is a trend towards increasingly large passenger aircraft, for which it is desirable to have correspondingly large wing spans. However, the maximum aircraft span is effectively limited by airport operating rules which govern various clearances required when manoeuvring around the airport (such as the span and/or ground clearance required for gate entry and safe taxiway usage).
In some suggested designs, aircraft are provided with wing tip devices which may be folded to reduce the span of the aircraft on the ground (compared to when the aircraft is configured for flight). However, there are technical challenges in providing a practical form of folding arrangement. Amongst the issues to be addressed are: the problem of providing a reliable hinge mechanism for accommodating the folding and unfolding of the wing tip device without impacting unduly on the design of the wing; and the problem of providing a compact and lightweight drive to effect the folding of the wing tip device. The present invention seeks to mitigate at least some of the above-mentioned problems.